1 599 116 BETA-CELL DIFFERENTIATION STATUS IN TYPE 2 DIABETES. TYPE 2 DIABETES (T2D) AFFECTS 415 MILLION PEOPLE WORLDWIDE AND IS CHARACTERIZED BY CHRONIC HYPERGLYCAEMIA AND INSULIN RESISTANCE, PROGRESSING TO INSUFFICIENT INSULIN PRODUCTION, AS A RESULT OF BETA-CELL FAILURE. OVER TIME, CHRONIC HYPERGLYCAEMIA CAN ULTIMATELY LEAD TO LOSS OF BETA-CELL FUNCTION, LEAVING PATIENTS INSULIN-DEPENDENT. UNTIL RECENTLY THE LOSS OF BETA-CELL MASS SEEN IN T2D WAS CONSIDERED TO BE THE RESULT OF INCREASED RATES OF APOPTOSIS; HOWEVER, IT HAS BEEN PROPOSED THAT APOPTOSIS ALONE CANNOT ACCOUNT FOR THE EXTENT OF BETA-CELL MASS LOSS SEEN IN THE DISEASE, AND THAT A LOSS OF FUNCTION MAY ALSO OCCUR AS A RESULT OF CHANGES IN BETA-CELL DIFFERENTIATION STATUS. IN THE PRESENT REVIEW, WE CONSIDER CURRENT KNOWLEDGE OF DETERMINANTS OF BETA-CELL FATE IN THE CONTEXT OF UNDERSTANDING ITS RELEVANCE TO DISEASE PROCESS IN T2D, AND ALSO THE IMPACT OF A DIABETOGENIC ENVIRONMENT (HYPERGLYCAEMIA, HYPOXIA, INFLAMMATION AND DYSLIPIDAEMIA) ON THE EXPRESSION OF GENES INVOLVED IN MAINTENANCE OF BETA-CELL IDENTITY. WE DESCRIBE CURRENT KNOWLEDGE OF THE IMPACT OF THE DIABETIC MICROENVIRONMENT ON GENE REGULATORY PROCESSES SUCH ALTERNATIVE SPLICING, THE EXPRESSION OF DISALLOWED GENES AND EPIGENETIC MODIFICATIONS. ELUCIDATING THE MOLECULAR MECHANISMS THAT UNDERPIN CHANGES TO BETA-CELL DIFFERENTIATION STATUS AND THE CONCOMITANT BETA-CELL FAILURE OFFERS POTENTIAL TREATMENT TARGETS FOR THE FUTURE MANAGEMENT OF PATIENTS WITH T2D. 2016 2 2178 37 EPIGENETIC MECHANISMS OF MACROPHAGE ACTIVATION IN TYPE 2 DIABETES. THE ALARMING RISE OF OBESITY AND TYPE 2 DIABETES (T2D) HAS PUT A TREMENDOUS STRAIN ON GLOBAL HEALTHCARE SYSTEMS. OVER THE PAST DECADE EXTENSIVE RESEARCH HAS FOCUSED ON THE ROLE OF MACROPHAGES AS KEY MEDIATORS OF INFLAMMATION IN T2D. THE INFLAMMATORY ENVIRONMENT IN THE OBESE ADIPOSE TISSUE AND PANCREATIC BETA-CELL ISLETS CREATES AND PERPETUATES IMBALANCED INFLAMMATORY MACROPHAGE ACTIVATION. CONSEQUENCES OF THIS CHRONIC LOW-GRADE INFLAMMATION INCLUDE INSULIN RESISTANCE IN THE ADIPOSE TISSUE AND PANCREATIC BETA-CELL DYSFUNCTION. RECENTLY, THE EMERGING FIELD OF EPIGENETICS HAS PROVIDED NEW INSIGHTS INTO THE PATHOGENESIS OF T2D, WHILE ALSO AFFORDING POTENTIAL NEW OPPORTUNITIES FOR TREATMENT. IN MACROPHAGES, EPIGENETIC MECHANISMS ARE INCREASINGLY BEING RECOGNIZED AS CRUCIAL CONTROLLERS OF THEIR PHENOTYPE. HERE, WE FIRST DESCRIBE THE ROLE OF MACROPHAGES IN T2D. THEN WE ELABORATE ON EPIGENETIC MECHANISMS THAT REGULATE MACROPHAGE ACTIVATION, THEREBY FOCUSING ON T2D. NEXT, WE HIGHLIGHT HOW DIABETIC CONDITIONS SUCH AS HYPERLIPIDEMIA AND HYPERGLYCEMIA COULD INDUCE EPIGENETIC CHANGES THAT PROMOTE AN INFLAMMATORY MACROPHAGE PHENOTYPE. IN CONCLUSION WE DISCUSS POSSIBLE THERAPEUTIC INTERVENTIONS BY TARGETING MACROPHAGE EPIGENETICS AND SPECULATE ON FUTURE RESEARCH DIRECTIONS. 2017 3 4263 38 MICRO(RNA) MANAGEMENT AND MISMANAGEMENT OF THE ISLET. PANCREATIC BETA-CELLS LOCATED WITHIN THE ISLETS OF LANGERHANS PLAY A CENTRAL ROLE IN METABOLIC CONTROL. THE MAIN FUNCTION OF THESE CELLS IS TO PRODUCE AND SECRETE INSULIN IN RESPONSE TO A RISE IN CIRCULATING LEVELS OF GLUCOSE AND OTHER NUTRIENTS. THE RELEASE OF INSUFFICIENT INSULIN TO COVER THE ORGANISM NEEDS RESULTS IN CHRONIC HYPERGLYCEMIA AND DIABETES DEVELOPMENT. BETA-CELLS INSURE A HIGHLY SPECIALIZED TASK AND TO EFFICIENTLY ACCOMPLISH THEIR FUNCTION THEY NEED TO EXPRESS A SPECIFIC SET OF GENES. MICRORNAS (MIRNAS) ARE SMALL NONCODING RNAS AND KEY REGULATORS OF GENE EXPRESSION. INDEED, BY PARTIALLY PAIRING TO SPECIFIC SEQUENCES IN THE 3' UNTRANSLATED REGIONS OF TARGET MRNAS, EACH OF THEM CAN CONTROL THE TRANSLATION OF HUNDREDS OF TRANSCRIPTS. IN THIS REVIEW, WE FOCUS ON FEW KEY MIRNAS CONTROLLING ISLET FUNCTION AND DISCUSS: THEIR DIFFERENTIAL EXPRESSION IN TYPE 2 DIABETES (T2D), THEIR REGULATION BY GENETIC AND ENVIRONMENTAL FACTORS, AND THEIR THERAPEUTIC POTENTIAL. GENETIC AND EPIGENETIC CHANGES OR PROLONGED EXPOSURE TO HYPERGLYCEMIA AND/OR HYPERLIPIDEMIA CAN AFFECT THE BETA-CELL MIRNA EXPRESSION PROFILE, RESULTING IN IMPAIRED BETA-CELL FUNCTION AND SURVIVAL LEADING TO THE DEVELOPMENT OF T2D. EXPERIMENTAL APPROACHES PERMITTING TO CORRECT THE LEVEL OF MISEXPRESSED MIRNAS HAVE BEEN SHOWN TO PREVENT OR TREAT T2D IN ANIMAL MODELS, SUGGESTING THAT THESE SMALL RNAS MAY BECOME INTERESTING THERAPEUTIC TARGETS. HOWEVER, TRANSLATION OF THESE EXPERIMENTAL FINDINGS TO THE CLINICS WILL NECESSITATE THE DEVELOPMENT OF INNOVATIVE STRATEGIES ALLOWING SAFE AND SPECIFIC DELIVERY OF COMPOUNDS MODULATING THE LEVEL OF THE RELEVANT MIRNAS TO THE BETA-CELLS. 2020 4 776 38 CELL- AND TISSUE-SPECIFIC EPIGENETIC CHANGES ASSOCIATED WITH CHRONIC INFLAMMATION IN INSULIN RESISTANCE AND TYPE 2 DIABETES MELLITUS. TYPE 2 DIABETES MELLITUS (T2DM) IS A CHRONIC METABOLIC DISORDER CHARACTERIZED BY HYPERGLYCAEMIA, WHICH CAN CAUSE MICRO- AND MACROVASCULAR COMPLICATIONS. CHRONIC INFLAMMATION MAY BE THE CAUSE AND RESULT OF T2DM, AND ITS RELATED COMPLICATIONS AS AN IMBALANCE BETWEEN PRO- AND ANTI-INFLAMMATORY CYTOKINES CAN AFFECT IMMUNE FUNCTIONS. APART FROM GENETIC CHANGES OCCURRING WITHIN THE BODY RESULTING IN INFLAMMATION IN T2DM, EPIGENETIC MODIFICATIONS CAN MODIFY GENE EXPRESSION IN RESPONSE TO ENVIRONMENTAL CUES SUCH AS AN UNHEALTHY DIET, LACK OF EXERCISE AND OBESITY. THE MOST WIDELY STUDIED EPIGENETIC MODIFICATION, DNA METHYLATION (DNAM), REGULATES GENE EXPRESSION AND MAY MANIPULATE INFLAMMATORY GENES TO INCREASE OR DECREASE INFLAMMATION ASSOCIATED WITH T2DM. THIS REVIEW EXPLORES THE STUDIES RELATED TO EPIGENETIC CHANGES, MORE SPECIFICALLY DNAM, ASSOCIATED WITH CHRONIC INFLAMMATION IN T2DM, AT BOTH THE CELL AND TISSUE LEVELS. STUDYING EPIGENETIC ALTERATIONS DURING INFLAMMATORY RESPONSE, AS A RESULT OF GENETIC AND ENVIRONMENTAL SIGNALS, CREATES OPPORTUNITIES FOR THE DEVELOPMENT OF "EARLY DETECTION/RELATIVE RISK" TESTS TO AID IN PREVENTION OF T2DM. UNDERSTANDING INFLAMMATION IN T2DM AT THE GENE LEVEL IN INFLAMMATION-ASSOCIATED CELLS AND TISSUES MAY PROVIDE FURTHER INSIGHT FOR THE DEVELOPMENT OF SPECIFIC THERAPEUTIC TARGETS FOR THE DISORDER. 2018 5 6200 36 THE INFLAMMATORY EFFECT OF EPIGENETIC FACTORS AND MODIFICATIONS IN TYPE 2 DIABETES. INFLAMMATION HAS A CENTRAL ROLE IN THE ETIOLOGY OF TYPE 2 DIABETES (T2D) AND ITS COMPLICATIONS. BOTH GENETIC AND EPIGENETIC FACTORS HAVE BEEN IMPLICATED IN THE DEVELOPMENT OF T2D-ASSOCIATED INFLAMMATION. EPIGENETIC MECHANISMS REGULATE THE FUNCTION OF SEVERAL COMPONENTS OF THE IMMUNE SYSTEM. DIABETIC CONDITIONS TRIGGER ABERRANT EPIGENETIC ALTERATIONS THAT CONTRIBUTE TO THE PROGRESSION OF INSULIN RESISTANCE AND BETA-CELL DYSFUNCTION BY INDUCTION OF INFLAMMATORY RESPONSES. THUS, TARGETING EPIGENETIC FACTORS AND MODIFICATIONS, AS ONE OF THE UNDERLYING CAUSES OF INFLAMMATION, COULD LEAD TO THE DEVELOPMENT OF NOVEL IMMUNE-BASED STRATEGIES FOR THE TREATMENT OF T2D. THE AIM OF THIS REVIEW IS TO PROVIDE AN OVERVIEW OF THE EPIGENETIC MECHANISMS INVOLVED IN THE PROPAGATION AND PERPETUATION OF CHRONIC INFLAMMATION IN T2D. WE ALSO DISCUSS THE POSSIBLE ANTI-INFLAMMATORY APPROACHES THAT TARGET EPIGENETIC FACTORS FOR THE TREATMENT OF T2D. 2020 6 2964 29 GENETIC AND EPIGENETIC MECHANISMS UNDERLYING ARSENIC-ASSOCIATED DIABETES MELLITUS: A PERSPECTIVE OF THE CURRENT EVIDENCE. CHRONIC EXPOSURE TO ARSENIC HAS BEEN ASSOCIATED WITH THE DEVELOPMENT OF DIABETES MELLITUS (DM), A DISEASE CHARACTERIZED BY HYPERGLYCEMIA RESULTING FROM DYSREGULATION OF GLUCOSE HOMEOSTASIS. THIS REVIEW SUMMARIZES FOUR MAJOR MECHANISMS BY WHICH ARSENIC INDUCES DIABETES, NAMELY INHIBITION OF INSULIN-DEPENDENT GLUCOSE UPTAKE, PANCREATIC BETA-CELL DAMAGE, PANCREATIC BETA-CELL DYSFUNCTION AND STIMULATION OF LIVER GLUCONEOGENESIS THAT ARE SUPPORTED BY BOTH IN VIVO AND IN VITRO STUDIES. ADDITIONALLY, THE ROLE OF POLYMORPHIC VARIANTS ASSOCIATED WITH ARSENIC TOXICITY AND DISEASE SUSCEPTIBILITY, AS WELL AS EPIGENETIC MODIFICATIONS ASSOCIATED WITH ARSENIC EXPOSURE, ARE CONSIDERED IN THE CONTEXT OF ARSENIC-ASSOCIATED DM. TAKEN TOGETHER, IN VITRO, IN VIVO AND HUMAN GENETIC/EPIGENETIC STUDIES SUPPORT THAT ARSENIC HAS THE POTENTIAL TO INDUCE DM PHENOTYPES AND IMPAIR KEY PATHWAYS INVOLVED IN THE REGULATION OF GLUCOSE HOMEOSTASIS. 2017 7 6341 27 THE ROLE OF EPIGENETIC MODIFICATIONS IN LATE COMPLICATIONS IN TYPE 1 DIABETES. TYPE 1 DIABETES IS A CHRONIC AUTOIMMUNE DISEASE IN WHICH THE DESTRUCTION OF PANCREATIC BETA CELLS LEADS TO HYPERGLYCEMIA. THE PREVENTION OF HYPERGLYCEMIA IS VERY IMPORTANT TO AVOID OR AT LEAST POSTPONE THE DEVELOPMENT OF MICRO- AND MACROVASCULAR COMPLICATIONS, ALSO KNOWN AS LATE COMPLICATIONS. THESE INCLUDE DIABETIC RETINOPATHY, CHRONIC RENAL FAILURE, DIABETIC NEUROPATHY, AND CARDIOVASCULAR DISEASES. THE IMPACT OF LONG-TERM HYPERGLYCEMIA HAS BEEN SHOWN TO PERSIST LONG AFTER THE NORMALIZATION OF BLOOD GLUCOSE LEVELS, A PHENOMENON KNOWN AS METABOLIC MEMORY. IT IS BELIEVED THAT EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS, AND MICRORNAS, PLAY AN IMPORTANT ROLE IN METABOLIC MEMORY. THE AIM OF THIS REVIEW IS TO ADDRESS THE IMPACT OF LONG-TERM HYPERGLYCEMIA ON EPIGENETIC MARKS IN LATE COMPLICATIONS OF TYPE 1 DIABETES. 2022 8 3748 41 INSIGHTS INTO THE ROLE OF DNA METHYLATION AND PROTEIN MISFOLDING IN DIABETES MELLITUS. BACKGROUND: DIABETES MELLITUS IS A METABOLIC DISORDER THAT IS CHARACTERIZED BY IMPAIRED GLUCOSE TOLERANCE RESULTING FROM DEFECTS IN INSULIN SECRETION, INSULIN ACTION, OR BOTH. EPIGENETIC MODIFICATIONS, WHICH ARE DEFINED AS INHERITED CHANGES IN GENE EXPRESSION THAT OCCUR WITHOUT CHANGES IN GENE SEQUENCE, ARE INVOLVED IN THE ETIOLOGY OF DIABETES. METHODS: IN THIS REVIEW, WE FOCUSED ON THE ROLE OF DNA METHYLATION AND PROTEIN MISFOLDING AND THEIR CONTRIBUTION TO THE DEVELOPMENT OF BOTH TYPE 1 AND TYPE 2 DIABETES MELLITUS. RESULTS: CHANGES IN DNA METHYLATION IN PARTICULAR ARE HIGHLY ASSOCIATED WITH THE DEVELOPMENT OF DIABETES. PROTEIN FUNCTION IS DEPENDENT ON THEIR PROPER FOLDING IN THE ENDOPLASMIC RETICULUM. DEFECTIVE PROTEIN FOLDING AND CONSEQUENTLY THEIR FUNCTIONS HAVE ALSO BEEN REPORTED TO PLAY A ROLE. EARLY TREATMENT OF DIABETES HAS PROVEN TO BE OF GREAT BENEFIT, AS EVEN TRANSIENT HYPERGLYCEMIA MAY LEAD TO PATHOLOGICAL EFFECTS AND COMPLICATIONS LATER ON. THIS HAS BEEN EXPLAINED BY THE THEORY OF THE DEVELOPMENT OF A METABOLIC MEMORY IN DIABETES. THE BASIS FOR THIS METABOLIC MEMORY WAS ATTRIBUTED TO OXIDATIVE STRESS, CHRONIC INFLAMMATION, NON-ENZYMATIC GLYCATION OF PROTEINS AND IMPORTANTLY, EPIGENETIC CHANGES. THIS HIGHLIGHTS THE IMPORTANCE OF LINKING NEW THERAPEUTICS TARGETING EPIGENETIC MECHANISMS WITH TRADITIONAL ANTIDIABETIC DRUGS. CONCLUSION: ALTHOUGH NEW DATA IS EVOLVING ON THE RELATION BETWEEN DNA METHYLATION, PROTEIN MISFOLDING, AND THE ETIOLOGY OF DIABETES, MORE STUDIES ARE REQUIRED FOR DEVELOPING NEW RELEVANT DIAGNOSTICS AND THERAPEUTICS. 2019 9 2549 34 EPIGENETICS IN OBESITY AND DIABETES MELLITUS: NEW INSIGHTS. A LONG-TERM COMPLICATION OF OBESITY IS THE DEVELOPMENT OF TYPE 2 DIABETES (T2D). PATIENTS WITH T2D HAVE BEEN DESCRIBED AS HAVING EPIGENETIC MODIFICATIONS. EPIGENETICS IS THE POST-TRANSCRIPTIONAL MODIFICATION OF DNA OR ASSOCIATED FACTORS CONTAINING GENETIC INFORMATION. THESE ENVIRONMENTALLY-INFLUENCED MODIFICATIONS, MAINTAINED DURING CELL DIVISION, CAUSE STABLE CHANGES IN GENE EXPRESSION. EPIGENETIC MODIFICATIONS OF T2D ARE DNA METHYLATION, ACETYLATION, UBIQUITYLATION, SUMOYLATION, AND PHOSPHORYLATION AT THE LYSINE RESIDUE AT THE AMINO TERMINUS OF HISTONES, AFFECTING DNA, HISTONES, AND NON-CODING RNA. DNA METHYLATION HAS BEEN SHOWN IN PANCREATIC ISLETS, ADIPOSE TISSUE, SKELETAL MUSCLE, AND THE LIVER. FURTHERMORE, EPIGENETIC CHANGES HAVE BEEN OBSERVED IN CHRONIC COMPLICATIONS OF T2D, SUCH AS DIABETIC NEPHROPATHY, DIABETIC RETINOPATHY, AND DIABETIC NEUROPATHY. RECENTLY, A NEW DRUG HAS BEEN DEVELOPED WHICH ACTS ON BROMODOMAINS AND EXTRATERMINAL (BET) DOMAIN PROTEINS, WHICH OPERATE LIKE EPIGENETIC READERS AND COMMUNICATE WITH CHROMATIN TO MAKE DNA ACCESSIBLE FOR TRANSCRIPTION BY INHIBITING THEM. THIS DRUG (APABETALONE) IS BEING STUDIED TO PREVENT MAJOR ADVERSE CARDIOVASCULAR EVENTS IN PEOPLE WITH T2D, LOW HDL CHOLESTEROL, CHRONIC KIDNEY FAILURE, AND RECENT CORONARY EVENTS. THIS REVIEW AIMS TO DESCRIBE THE RELATIONSHIP BETWEEN OBESITY, LONG-TERM COMPLICATIONS SUCH AS T2D, AND EPIGENETIC MODIFICATIONS AND THEIR POSSIBLE TREATMENTS. 2023 10 6067 41 THE DIABETES MELLITUS-ATHEROSCLEROSIS CONNECTION: THE ROLE OF LIPID AND GLUCOSE METABOLISM AND CHRONIC INFLAMMATION. DIABETES MELLITUS COMPRISES A GROUP OF CARBOHYDRATE METABOLISM DISORDERS THAT SHARE A COMMON MAIN FEATURE OF CHRONIC HYPERGLYCEMIA THAT RESULTS FROM DEFECTS OF INSULIN SECRETION, INSULIN ACTION, OR BOTH. INSULIN IS AN IMPORTANT ANABOLIC HORMONE, AND ITS DEFICIENCY LEADS TO VARIOUS METABOLIC ABNORMALITIES IN PROTEINS, LIPIDS, AND CARBOHYDRATES. ATHEROSCLEROSIS DEVELOPS AS A RESULT OF A MULTISTEP PROCESS ULTIMATELY LEADING TO CARDIOVASCULAR DISEASE ASSOCIATED WITH HIGH MORBIDITY AND MORTALITY. ALTERATION OF LIPID METABOLISM IS A RISK FACTOR AND CHARACTERISTIC FEATURE OF ATHEROSCLEROSIS. POSSIBLE LINKS BETWEEN THE TWO CHRONIC DISORDERS DEPENDING ON ALTERED METABOLIC PATHWAYS HAVE BEEN INVESTIGATED IN NUMEROUS STUDIES. IT WAS SHOWN THAT BOTH TYPES OF DIABETES MELLITUS CAN ACTUALLY INDUCE ATHEROSCLEROSIS DEVELOPMENT OR FURTHER ACCELERATE ITS PROGRESSION. ELEVATED GLUCOSE LEVEL, DYSLIPIDEMIA, AND OTHER METABOLIC ALTERATIONS THAT ACCOMPANY THE DISEASE DEVELOPMENT ARE TIGHTLY INVOLVED IN THE PATHOGENESIS OF ATHEROSCLEROSIS AT ALMOST EVERY STEP OF THE ATHEROGENIC PROCESS. CHRONIC INFLAMMATION IS CURRENTLY CONSIDERED AS ONE OF THE KEY FACTORS IN ATHEROSCLEROSIS DEVELOPMENT AND IS PRESENT STARTING FROM THE EARLIEST STAGES OF THE PATHOLOGY INITIATION. IT MAY ALSO BE REGARDED AS ONE OF THE POSSIBLE LINKS BETWEEN ATHEROSCLEROSIS AND DIABETES MELLITUS. HOWEVER, THE DATA AVAILABLE SO FAR DO NOT ALLOW FOR DEVELOPING EFFECTIVE ANTI-INFLAMMATORY THERAPEUTIC STRATEGIES THAT WOULD STOP ATHEROSCLEROTIC LESION PROGRESSION OR INDUCE LESION REDUCTION. IN THIS REVIEW, WE SUMMARIZE THE MAIN ASPECTS OF DIABETES MELLITUS THAT POSSIBLY AFFECT THE ATHEROGENIC PROCESS AND ITS RELATIONSHIP WITH CHRONIC INFLAMMATION. WE ALSO DISCUSS THE ESTABLISHED PATHOPHYSIOLOGICAL FEATURES THAT LINK ATHEROSCLEROSIS AND DIABETES MELLITUS, SUCH AS OXIDATIVE STRESS, ALTERED PROTEIN KINASE SIGNALING, AND THE ROLE OF CERTAIN MIRNA AND EPIGENETIC MODIFICATIONS. 2020 11 1974 34 EPIGENETIC ALTERATIONS CAUSED BY NUTRITIONAL STRESS DURING FETAL PROGRAMMING OF THE ENDOCRINE PANCREAS. NUTRITION DURING CRITICAL PERIODS OF DEVELOPMENT IS ONE OF THE PIVOTAL FACTORS IN ESTABLISHING A LIFELONG HEALTHY METABOLISM. DIFFERENT NUTRITIONAL DEFICIENCIES SUCH AS A LOW AVAILABILITY OF PROTEINS IN THE MATERNAL DIET PRODUCE ALTERATIONS IN OFFSPRING THAT INCLUDE CHANGES IN INSULIN AND GLUCOSE METABOLISM, A DECREASE IN THE SIZE AND NUMBER OF CELLS OF PANCREATIC ISLETS OF LANGERHANS, AND PREMATURE AGEING OF THE SECRETORY FUNCTION OF PANCREATIC BETA CELLS. MOREOVER, IT HAS BEEN REPORTED THAT CHRONIC NUTRITIONAL STRESS IS ASSOCIATED WITH EPIGENETIC ALTERATIONS IN MECHANISMS OF GENE REGULATION DURING PANCREATIC DEVELOPMENT AND FUNCTION. THESE ALTERATIONS CAN LEAD TO DYSFUNCTIONAL STATES IN PANCREATIC BETA CELLS, WHICH IN THE LONG RUN ARE RESPONSIBLE FOR THE ONSET OF METABOLIC DISEASES LIKE TYPE 2 DIABETES. THE PRESENT REVIEW SUMMARIZES THE MOST IMPORTANT EVIDENCE IN RELATION TO THE PARTICIPATION OF EPIGENETIC MECHANISMS IN THE REGULATION OF GENE EXPRESSION DURING THE INTRAUTERINE PROGRAMMING OF THE ENDOCRINE PANCREAS IN ANIMAL MODELS. SUCH MECHANISMS INCLUDE DNA METHYLATION AS WELL AS MODIFICATIONS OF HISTONES AND MICRORNAS (MIRNAS). 2015 12 4891 38 OXIDATIVE STRESS AND INFLAMMATORY MARKERS IN PREDIABETES AND DIABETES. PREDIABETES IS A STATE OF ELEVATED PLASMA GLUCOSE IN WHICH THE THRESHOLD FOR DIABETES HAS NOT YET BEEN REACHED AND CAN PREDISPOSE TO THE DEVELOPMENT OF TYPE 2 DIABETES AND CARDIOVASCULAR DISEASES. INSULIN RESISTANCE AND IMPAIRED BETA-CELL FUNCTION ARE OFTEN ALREADY PRESENT IN PREDIABETES. HYPERGLYCEMIA CAN UPREGULATE MARKERS OF CHRONIC INFLAMMATION AND CONTRIBUTE TO INCREASED REACTIVE OXYGEN SPECIES (ROS) GENERATION, WHICH ULTIMATELY CAUSE VASCULAR DYSFUNCTION. CONVERSELY, INCREASED OXIDATIVE STRESS AND INFLAMMATION CAN LEAD TO INSULIN RESISTANCE AND IMPAIRED INSULIN SECRETION. PROPER TREATMENT OF HYPERGLYCEMIA AND INHIBITION OF ROS OVERPRODUCTION IS CRUCIAL FOR DELAYING ONSET OF DIABETES AND FOR PREVENTION OF CARDIOVASCULAR COMPLICATIONS. THUS, IT IS IMPERATIVE TO DETERMINE THE MECHANISMS INVOLVED IN THE PROGRESSION FROM PREDIABETES TO DIABETES INCLUDING A CLARIFICATION OF HOW OLD AND NEW MEDICATIONS AFFECT OXIDATIVE AND IMMUNE MECHANISMS OF DIABETES. IN THIS REVIEW, WE DISCUSS THE RELATIONSHIP BETWEEN OXIDATIVE STRESS AND HYPERGLYCEMIA ALONG WITH LINKS BETWEEN INFLAMMATION AND PREDIABETES. ADDITIONALLY, THE EFFECTS OF HYPERGLYCEMIC MEMORY, MICROVESICLES, MICRO-RNA, AND EPIGENETIC REGULATION ON INFLAMMATION, OXIDATIVE STATE, AND GLYCEMIC CONTROL ARE HIGHLIGHTED. ADIPOSE TISSUE AND THEIR INFLUENCE ON CHRONIC INFLAMMATION ARE ALSO BRIEFLY REVIEWED. FINALLY, THE ROLE OF IMMUNE-TARGETED THERAPIES AND ANTI-DIABETIC MEDICATION ON GLYCEMIC CONTROL AND OXIDATIVE STRESS ARE DISCUSSED. 2019 13 4425 43 MOLECULAR BASIS OF AGEING IN CHRONIC METABOLIC DISEASES. AIM: OVER THE LAST DECADES, THE SHIFT IN AGE DISTRIBUTION TOWARDS OLDER AGES AND THE PROGRESSIVE AGEING WHICH HAS OCCURRED IN MOST POPULATIONS HAVE BEEN PARALLELED BY A GLOBAL EPIDEMIC OF OBESITY AND ITS RELATED METABOLIC DISORDERS, PRIMARILY, TYPE 2 DIABETES (T2D). DYSFUNCTION OF THE ADIPOSE TISSUE (AT) IS WIDELY RECOGNIZED AS A SIGNIFICANT HALLMARK OF THE AGEING PROCESS THAT, IN TURN, RESULTS IN SYSTEMIC METABOLIC ALTERATIONS. THESE INCLUDE INSULIN RESISTANCE, ACCUMULATION OF ECTOPIC LIPIDS AND CHRONIC INFLAMMATION, WHICH ARE RESPONSIBLE FOR AN ELEVATED RISK OF OBESITY AND T2D ONSET ASSOCIATED TO AGEING. ON THE OTHER HAND, OBESITY AND T2D, THE PARADIGMS OF AT DYSFUNCTION, SHARE MANY PHYSIOLOGICAL CHARACTERISTICS WITH THE AGEING PROCESS, SUCH AS AN INCREASED BURDEN OF SENESCENT CELLS AND EPIGENETIC ALTERATIONS. THUS, THESE CHRONIC METABOLIC DISORDERS MAY REPRESENT A STATE OF ACCELERATED AGEING. MATERIALS AND METHODS: A MORE PRECISE EXPLANATION OF THE FUNDAMENTAL AGEING MECHANISMS THAT OCCUR IN AT AND A DEEPER UNDERSTANDING OF THEIR ROLE IN THE INTERPLAY BETWEEN ACCELERATED AGEING AND AT DYSFUNCTION CAN BE A FUNDAMENTAL LEAP TOWARDS NOVEL THERAPIES THAT ADDRESS THE CAUSES, NOT JUST THE SYMPTOMS, OF OBESITY AND T2D, UTILIZING STRATEGIES THAT TARGET EITHER SENESCENT CELLS OR DNA METHYLATION. RESULTS: IN THIS REVIEW, WE SUMMARIZE THE CURRENT KNOWLEDGE OF THE PATHWAYS THAT LEAD TO AT DYSFUNCTION IN THE CHRONOLOGICAL AGEING PROCESS AS WELL AS THE PATHOPHYSIOLOGY OF OBESITY AND T2D, EMPHASIZING THE CRITICAL ROLE OF CELLULAR SENESCENCE AND DNA METHYLATION. CONCLUSION: FINALLY, WE HIGHLIGHT THE NEED FOR FURTHER RESEARCH FOCUSED ON TARGETING THESE MECHANISMS. 2020 14 2163 35 EPIGENETIC MECHANISMS IN DIABETIC VASCULAR COMPLICATIONS. THERE HAS BEEN A RAPID INCREASE IN THE INCIDENCE OF DIABETES AS WELL THE ASSOCIATED VASCULAR COMPLICATIONS. BOTH GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN IMPLICATED IN THESE PATHOLOGIES. INCREASING EVIDENCE SUGGESTS THAT EPIGENETIC FACTORS PLAY A KEY ROLE IN THE COMPLEX INTERPLAY BETWEEN GENES AND THE ENVIRONMENT. ACTIONS OF MAJOR PATHOLOGICAL MEDIATORS OF DIABETES AND ITS COMPLICATIONS SUCH AS HYPERGLYCAEMIA, OXIDANT STRESS, AND INFLAMMATORY FACTORS CAN LEAD TO DYSREGULATED EPIGENETIC MECHANISMS THAT AFFECT CHROMATIN STRUCTURE AND GENE EXPRESSION. FURTHERMORE, PERSISTENCE OF THIS ALTERED STATE OF THE EPIGENOME MAY BE THE UNDERLYING MECHANISM CONTRIBUTING TO A 'METABOLIC MEMORY' THAT RESULTS IN CHRONIC INFLAMMATION AND VASCULAR DYSFUNCTION IN DIABETES EVEN AFTER ACHIEVING GLYCAEMIC CONTROL. FURTHER EXAMINATION OF EPIGENETIC MECHANISMS BY ALSO TAKING ADVANTAGE OF RECENTLY DEVELOPED NEXT-GENERATION SEQUENCING TECHNOLOGIES CAN PROVIDE NOVEL INSIGHTS INTO THE PATHOLOGY OF DIABETES AND ITS COMPLICATIONS AND LEAD TO THE DISCOVERY OF MUCH NEEDED NEW DRUG TARGETS FOR THESE DISEASES. IN THIS REVIEW, WE HIGHLIGHT THE ROLE OF EPIGENETICS IN DIABETES AND ITS VASCULAR COMPLICATIONS, AND RECENT TECHNOLOGICAL ADVANCES THAT HAVE SIGNIFICANTLY ACCELERATED THE FIELD. 2011 15 6335 34 THE ROLE OF DNA METHYLATION IN THE PATHOGENESIS OF TYPE 2 DIABETES MELLITUS. DIABETES MELLITUS (DM) IS A CHRONIC CONDITION CHARACTERISED BY BETA CELL DYSFUNCTION AND PERSISTENT HYPERGLYCAEMIA. THE DISORDER CAN BE DUE TO THE ABSENCE OF ADEQUATE PANCREATIC INSULIN PRODUCTION OR A WEAK CELLULAR RESPONSE TO INSULIN SIGNALLING. AMONG THE THREE TYPES OF DM, NAMELY, TYPE 1 DM (T1DM), TYPE 2 DM (T2DM), AND GESTATIONAL DM (GDM); T2DM ACCOUNTS FOR ALMOST 90% OF DIABETES CASES WORLDWIDE.EPIGENETIC TRAITS ARE STABLY HERITABLE PHENOTYPES THAT RESULT FROM CERTAIN CHANGES THAT AFFECT GENE FUNCTION WITHOUT ALTERING THE GENE SEQUENCE. WHILE EPIGENETIC TRAITS ARE CONSIDERED REVERSIBLE MODIFICATIONS, THEY CAN BE INHERITED MITOTICALLY AND MEIOTICALLY. IN ADDITION, EPIGENETIC TRAITS CAN RANDOMLY ARISE IN RESPONSE TO ENVIRONMENTAL FACTORS OR CERTAIN GENETIC MUTATIONS OR LESIONS, SUCH AS THOSE AFFECTING THE ENZYMES THAT CATALYSE THE EPIGENETIC MODIFICATION. IN THIS REVIEW, WE FOCUS ON THE ROLE OF DNA METHYLATION, A TYPE OF EPIGENETIC MODIFICATION, IN THE PATHOGENESIS OF T2DM. 2020 16 4195 37 METABOLIC MEMORY: MECHANISMS AND IMPLICATIONS FOR DIABETIC RETINOPATHY. CHRONIC HYPERGLYCEMIA OF DIABETES LEADS TO MICROVASCULAR COMPLICATIONS THAT SEVERELY IMPACT QUALITY OF LIFE. DIABETIC RETINOPATHY (DR) MAY BE THE MOST COMMON OF THESE AND IS A LEADING CAUSE OF VISUAL IMPAIRMENT AND BLINDNESS AMONG WORKING AGE ADULTS IN DEVELOPED NATIONS. MANY LARGE-SCALE TYPE 1 AND TYPE 2 DIABETES CLINICAL TRIALS HAVE DEMONSTRATED THAT EARLY INTENSIVE GLYCEMIC CONTROL CAN REDUCE THE INCIDENCE AND PROGRESSION OF MICRO AND MACROVASCULAR COMPLICATIONS. ON THE OTHER HAND, EPIDEMIOLOGICAL AND PROSPECTIVE DATA HAVE REVEALED THAT THE STRESSORS OF DIABETIC VASCULATURE PERSIST BEYOND THE POINT WHEN GLYCEMIC CONTROL HAS BEEN ACHIEVED. THESE KINDS OF PERSISTENT ADVERSE EFFECTS OF HYPERGLYCEMIA ON THE DEVELOPMENT AND PROGRESSION OF COMPLICATIONS HAS BEEN DEFINED AS "METABOLIC MEMORY", AND OXIDATIVE STRESS, ADVANCED GLYCATION END PRODUCTS AND EPIGENETIC CHANGES HAVE BEEN IMPLICATED IN THE PROCESS. RECENT STUDIES HAVE INDICATED THAT SUCH "HYPERGLYCEMIC MEMORY" MAY ALSO INFLUENCE DR, SUGGESTING THAT MANIPULATION OF HYPERGLYCEMIC MEMORY MAY PROVE A BENEFICIAL APPROACH TO PREVENTION AND TREATMENT. THIS REVIEW SUMMARIZES THE EVIDENCE FROM DR-RELATED CLINICAL TRIALS AND MECHANISTIC STUDIES TO INVESTIGATE THE SIGNIFICANCE OF METABOLIC MEMORY IN DR AND UNDERSTAND ITS POTENTIAL AS A TARGET OF MOLECULAR THERAPEUTICS AIMED AT REVERSING HYPERGLYCEMIC MEMORY. 2012 17 2190 37 EPIGENETIC MECHANISMS. THE INCIDENCE OF DIABETES AND RELATED COMPLICATIONS LIKE NEPHROPATHY IS GROWING RAPIDLY AND HAS BECOME A MAJOR HEALTH CARE ISSUE. CHANGES IN THE ENVIRONMENT AND NUTRITIONAL HABITS HAVE BEEN IMPLICATED AS MAJOR PLAYERS. FURTHERMORE, IT IS BECOMING INCREASINGLY CLEAR THAT EPIGENETIC FACTORS MAY MODULATE THE CONNECTIONS BETWEEN GENES AND THE ENVIRONMENT. WHILE DIABETES IN ITSELF IS TREATABLE TO A LARGE EXTENT, IT IS STILL ASSOCIATED WITH SIGNIFICANTLY INCREASED RISK FOR COMPLICATIONS INCLUDING CHRONIC KIDNEY AND CARDIOVASCULAR DISEASES. CURRENT TREATMENTS HAVE ADDED PREVENTATIVE APPROACHES SO AS TO AVOID FUTURE DIABETIC COMPLICATIONS. UNFORTUNATELY, DIABETIC PATIENTS ARE OFTEN PLAGUED WITH THE CONTINUED DEVELOPMENT OF VARIOUS COMPLICATIONS EVEN AFTER ACHIEVING GLUCOSE CONTROL. THIS HAS BEEN SUGGESTED TO BE ATTRIBUTABLE TO A MYSTERIOUS PHENOMENON TERMED 'METABOLIC MEMORY' OF THE PRIOR GLYCEMIC STATE. RECENT STUDIES HAVE SUGGESTED THAT EPIGENETIC CHANGES TO CHROMATIN CAN AFFECT GENE EXPRESSION IN RESPONSE TO VARIOUS STIMULI, AND CHANGES IN KEY BIOCHEMICAL PATHWAYS AND EPIGENETIC HISTONE AND DNA METHYLATION PATTERNS IN CHROMATIN HAVE BEEN OBSERVED IN A DIABETIC MILIEU. THESE ACCUMULATING DATA SUGGEST THAT METABOLIC OR HYPERGLYCEMIC MEMORY MAY BE DUE TO EPIGENETIC CHANGES IN SPECIFIC TARGET TISSUES ALTERING GENE EXPRESSION WITHOUT CHANGING THE GENETIC CODE ITSELF. WHILE THE GENETICS OF DIABETES HAS LONG BEEN THE FOCUS OF SCIENTIFIC RESEARCH, MUCH LESS IS KNOWN ABOUT THE ROLE OF EPIGENETICS AND THE RELATED MOLECULAR PATHWAYS THAT MIGHT AFFECT THE DEVELOPMENT OF DIABETES AND THE ASSOCIATED COMPLICATIONS. FURTHER STUDIES OF EPIGENETIC MECHANISMS ARE THEREFORE TIMELY AND COULD PROVIDE VALUABLE NEW INSIGHTS INTO THE PATHOLOGY OF DIABETIC COMPLICATIONS AND ALSO UNCOVER MUCH NEEDED NEW THERAPEUTIC TARGETS. 2011 18 44 38 A COMPREHENSIVE REVIEW ON HIGH -FAT DIET-INDUCED DIABETES MELLITUS: AN EPIGENETIC VIEW. MODERN LIFESTYLE, GENETICS, NUTRITIONAL OVERLOAD THROUGH HIGH-FAT DIET ATTRIBUTED PREVALENCE AND DIABETES OUTCOMES WITH VARIOUS COMPLICATIONS PRIMARILY DUE TO OBESITY IN WHICH ENERGY-DENSE DIETS FREQUENTLY AFFECT METABOLIC HEALTH. ONE POSSIBLE ISSUE USUALLY ASSOCIATED WITH ELEVATED CHRONIC FAT INTAKE IS INSULIN RESISTANCE, AND HYPERGLYCEMIA CONSTITUTES AN IMPORTANT FUNCTION IN ALTERING THE CARBOHYDRATES AND LIPIDS METABOLISM. SIMILARLY, IN ASSESSING HUMAN SUSCEPTIBILITY TO WEIGHT GAIN AND OBESITY, GENETIC VARIATIONS PLAY A CENTRAL ROLE, CONTRIBUTING TO KEEN INTEREST IN IDENTIFYING THE POSSIBLE ROLE OF EPIGENETICS AS A MEDIATOR OF GENE-ENVIRONMENTAL INTERACTIONS INFLUENCING THE PRODUCTION OF TYPE 2 DIABETES MELLITUS AND ITS RELATED CONCERNS. EPIGENETIC MODIFICATIONS ASSOCIATED WITH THE ACCEPTANCE OF A SEDENTARY LIFESTYLE AND ENVIRONMENTAL STRESS FACTORS IN RESPONSE TO ENERGY INTAKE AND EXPENDITURE IMBALANCES COMPLEMENT GENETIC ALTERATIONS AND LEAD TO THE PRODUCTION AND ADVANCEMENT OF METABOLIC DISORDERS SUCH AS DIABETES AND OBESITY. METHYLATION OF DNA, HISTONE MODIFICATIONS, AND INCREASES IN THE EXPRESSION OF NON-CODING RNAS CAN RESULT IN REDUCED TRANSCRIPTIONAL ACTIVITY OF KEY BETA-CELL GENES THUS CREATING INSULIN RESISTANCE. EPIGENETICS CONTRIBUTE TO CHANGES IN THE EXPRESSION OF THE UNDERLYING INSULIN RESISTANCE AND INSUFFICIENCY GENE NETWORKS, ALONG WITH LOW-GRADE OBESITY-RELATED INFLAMMATION, INCREASED ROS GENERATION, AND DNA DAMAGE IN MULTIORGANS. THIS REVIEW FOCUSED ON EPIGENETIC MECHANISMS AND METABOLIC REGULATIONS ASSOCIATED WITH HIGH-FAT DIET (HFD)-INDUCED DIABETES MELLITUS. 2022 19 2613 38 EPIGENETICS: DECIPHERING ITS ROLE IN DIABETES AND ITS CHRONIC COMPLICATIONS. 1. INCREASING EVIDENCE SUGGESTS THAT EPIGENETIC FACTORS MIGHT REGULATE THE COMPLEX INTERPLAY BETWEEN GENES AND THE ENVIRONMENT, AND AFFECT HUMAN DISEASES, SUCH AS DIABETES AND ITS COMPLICATIONS. 2. CLINICAL TRIALS HAVE UNDERSCORED THE LONG LASTING BENEFICIAL EFFECTS OF STRICT GLYCAEMIC CONTROL FOR REDUCING THE PROGRESSION OF DIABETIC COMPLICATIONS. THEY HAVE ALSO SHOWN THAT DIABETIC COMPLICATIONS, SUCH AS DIABETIC NEPHROPATHY, A CHRONIC KIDNEY DISORDER, CAN CONTINUE EVEN AFTER BLOOD GLUCOSE NORMALIZATION, SUGGESTING A METABOLIC MEMORY OF THE PRIOR GLYCAEMIC STATE. 3. DYSREGULATION OF EPIGENETIC POST-TRANSCRIPTIONAL MODIFICATIONS OF HISTONES IN CHROMATIN, INCLUDING HISTONE LYSINE METHYLATION, HAS BEEN IMPLICATED IN ABERRANT GENE REGULATION ASSOCIATED WITH THE PATHOLOGY OF DIABETES AND ITS COMPLICATIONS. GENOME-WIDE STUDIES HAVE SHOWN CELL-TYPE SPECIFIC CHANGES IN HISTONE METHYLATION PATTERNS UNDER DIABETIC CONDITIONS. IN ADDITION, STUDIES IN VASCULAR CELLS HAVE SHOWN LONG LASTING CHANGES IN EPIGENETIC MODIFICATIONS AT KEY INFLAMMATORY GENE PROMOTERS AFTER PRIOR EXPOSURE TO DIABETIC CONDITIONS, SUGGESTING A POSSIBLE MECHANISM FOR METABOLIC MEMORY. 4. RECENT STUDIES HAVE SHOWN ROLES FOR HISTONE METHYLATION, DNA METHYLATION, AS WELL AS MICRORNA IN DIABETIC NEPHROPATHY. WHETHER THESE EPIGENETIC FACTORS PLAY A ROLE IN METABOLIC MEMORY OF DIABETIC KIDNEY DISEASE IS LESS WELL UNDERSTOOD. 5. THE INCIDENCE OF DIABETES IS GROWING RAPIDLY, AS ALSO THE COST OF TREATING THE RESULTING COMPLICATIONS. A BETTER UNDERSTANDING OF METABOLIC MEMORY AND THE POTENTIAL INVOLVEMENT OF EPIGENETIC MECHANISMS IN THIS PHENOMENON COULD ENABLE THE DEVELOPMENT OF NEW THERAPEUTIC TARGETS FOR THE TREATMENT AND/OR PREVENTION OF SUSTAINED DIABETIC COMPLICATIONS. 2011 20 2491 31 EPIGENETICS AND CARDIOVASCULAR DISEASE IN DIABETES. TYPE 2 DIABETES HAS BECOME A MAJOR HEALTH ISSUE WORLDWIDE. CHRONIC HYPERGLYCEMIA INDUCES A LOW-GRADE INFLAMMATION THAT, ON TOP OF OTHER MECHANISMS, LEADS TO ENDOTHELIAL DYSFUNCTION. MOUNTING EVIDENCE SUGGESTS THAT DNA METHYLATION, POST-TRANSLATIONAL MODIFICATIONS OF HISTONES, AND LONG NON-CODING RNAS PLAY AN IMPORTANT ROLE IN THE INITIATION, MAINTENANCE, AND PROGRESSION OF BOTH MACRO- AND MICRO-VASCULAR COMPLICATIONS OF DIABETES. LONG-TERM EXPOSURE TO HYPERGLYCEMIA INDUCES EPIGENETIC CHANGES THAT COULD BECOME IRREVERSIBLE, A PHENOMENON KNOWN AS THE 'METABOLIC MEMORY.' WHETHER EPIGENETIC-BASED THERAPIES COULD BE USED TO SLOW OR LIMIT THE PROGRESSION OF CARDIOVASCULAR DISEASE REMAINS UNCLEAR. WHILE NON-CODING RNAS ARE CURRENTLY INVESTIGATED AS POTENTIAL BIOMARKERS THAT PREDICT DIABETIC CARDIOVASCULAR DISEASE INCIDENCE AND PROGRESSION, THEIR THERAPEUTIC ROLE IS ONLY HYPOTHETICAL. IN THIS REVIEW, WE HIGHLIGHT THE LATEST FINDINGS IN EXPERIMENTAL AND CLINICAL STUDIES RELEVANT TO EPIGENETICS AND CARDIOVASCULAR DISEASE IN DIABETES. 2015